How do you calculate chiplet assembly yield?

Divide good assemblies by total assemblies attempted and multiply by 100. With 8 good out of 250 attempted, that is 8 ÷ 250 × 100 = 3.2%.

What is a good chiplet assembly yield?

For mature 2.5D/3D lines a per-step assembly yield of 95-99% is expected, since a module stacking several chiplets needs each step high to keep composite yield viable. A 3.2% result like the default signals a line still in bring-up or a serious process excursion.

Why is my chiplet yield so much lower than wafer yield?

Chiplet modules multiply risk: each die placement, micro-bump, and bond is an independent chance to fail, so even 99% per interconnect can drop composite yield fast across thousands of bumps.

What does the gap-to-target value mean?

It is your actual yield minus your target in percentage points. Here 3.2% against a 95% target gives a 91.8-point gap, meaning the process is far below where it must run to be profitable.

Chiplet assembly yield vs known-good-die yield — what's the difference?

Known-good-die yield measures dies proven good before assembly; assembly yield measures how many survive being joined into the module. You can start with 100% KGD and still lose units during bonding and warpage.

How many units do I need before the yield number is trustworthy?

A handful of units gives a directional read only. For a stable estimate at 95%+ yields you typically want a few hundred to a few thousand assemblies so a single failure doesn't swing the percentage.

Semiconductor Advanced Packaging & Test calculator

Chiplet Assembly Yield Calculator

Chiplet assembly yield is the share of multi-die packages that survive placement, bonding, and interconnect formation without a defect that fails final inspection or test. Advanced-packaging process engineers, OSAT yield teams, and 2.5D/3D module owners track it because every added chiplet compounds the loss: a module with several known-good dies can still fail on a single bad micro-bump or warpage-induced open. Because chiplet architectures replace one big monolithic die with many smaller ones stitched together, assembly yield often becomes the dominant cost driver rather than wafer defect density. Watching yield against a target tells you whether the line is capable or whether bonding, underfill, or handling needs attention before you scale.

What this calculator does

Estimate chiplet assembly yield for semiconductor advanced packaging and test using production-ready inputs so teams can track KPI performance and decide whether corrective action is needed.
Use it when chiplet assembly yield in semiconductor advanced packaging and test needs a clean rate and gap-to-target you can put on a tier board.
It computes the percentage of chiplet assemblies that pass out of the total attempted, plus how many points that rate sits above or below your target.

Formula used

Chiplet assembly yield rate = chiplet assembly yield count ÷ total chiplet assembly yield population × 100
Chiplet assembly yield gap to target = chiplet assembly yield rate - target chiplet assembly yield rate

Inputs explained

Good chiplet assemblies passing final AOI:
Total chiplet assemblies attempted on the module:
Target chiplet assembly yield rate:

How to use the result

Use it after each build lot or process change to gauge whether die-attach, hybrid bonding, or reflow is holding your composite-yield budget.
A single lot yield can be noisy on low volumes and does not distinguish placement defects from interconnect or warpage failures, so pair it with defect Pareto data before acting.

Current U.S. benchmarks

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The producer price index for plastic resins and materials stands at 319.371 (BLS, May 2026), up 19.5% from a year earlier. Quotes priced off last quarter's material cost miss this move.
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Common questions

How do you calculate chiplet assembly yield? Divide good assemblies by total assemblies attempted and multiply by 100. With 8 good out of 250 attempted, that is 8 ÷ 250 × 100 = 3.2%.
What is a good chiplet assembly yield? For mature 2.5D/3D lines a per-step assembly yield of 95-99% is expected, since a module stacking several chiplets needs each step high to keep composite yield viable. A 3.2% result like the default signals a line still in bring-up or a serious process excursion.
Why is my chiplet yield so much lower than wafer yield? Chiplet modules multiply risk: each die placement, micro-bump, and bond is an independent chance to fail, so even 99% per interconnect can drop composite yield fast across thousands of bumps.
What does the gap-to-target value mean? It is your actual yield minus your target in percentage points. Here 3.2% against a 95% target gives a 91.8-point gap, meaning the process is far below where it must run to be profitable.
Chiplet assembly yield vs known-good-die yield — what's the difference? Known-good-die yield measures dies proven good before assembly; assembly yield measures how many survive being joined into the module. You can start with 100% KGD and still lose units during bonding and warpage.

Last reviewed 2026-05-12.